1. Field of the Invention
The present invention relates to an apparatus and method for providing an internet protocol (IP) level connectivity between internet access terminals using a service gateway, and more particularly to an apparatus and method which enables a subscriber terminal connected to an internet while having an inherent Internet Protocol (hereinbelow, referred to as xe2x80x9cIPxe2x80x9d) address to communicate with a dial-up internet access terminal which has been allocated with no inherent IP address by establishing an IP level connectivity at any time.
2. Description of the Related Art
Currently, due to the rapid growth of the internet and developments of high speed internet access technology based on an Asynchronous Transfer Mode Protocol (hereinbelow, referred to as xe2x80x9cATMxe2x80x9d) and Asymmetric Digital Subscriber Line Mode Protocol (hereinbelow, referred to as xe2x80x9cADSLxe2x80x9d), an IP fax through the internet and Internet Telephony (hereinbelow, referred to as xe2x80x9cITxe2x80x9d) are becoming influential communication services.
Such services require communication environment which always enables to be connected to an opposite subscriber terminal like a Plain Old Telephone Service (hereinbelow, referred to as xe2x80x9cPOTSxe2x80x9d) or a dial tone service.
The communication environment can be built when two subscriber terminals are connected to the internet and an IP level connectivity between the terminals is provided.
Namely, under the communication environment in which two subscriber terminals are connected to the internet while each having an inherent IP address, and the establishment of the connection to even an IP hierarchy between the terminals through the internet enables transmission/reception of an IP packet, only mutual identification of the IP address of an opposite subscriber terminal is needed to initiate an IT service.
However, in this case, a terminal (hereinbelow, referred to as a xe2x80x9csource terminalxe2x80x9d) initiating the IT service has been connected to the internet while having an inherent IP address, whereas an opposite terminal (hereinbelow, referred to as a xe2x80x9ctarget terminalxe2x80x9d) is a dial-up terminal connected to the internet while being dynamically allocated to an IP address from an Internet Service Provider (hereinbelow, referred to as xe2x80x9cISPxe2x80x9d), which may have not been connected to the internet.
At this point, establishment of an IP level connectivity between two terminals requires that an ISP providing the target terminal with an internet access service identifies the target terminal, which is followed by establishing a Point-to Point Protocol (hereinbelow, referred to as xe2x80x9cPPPxe2x80x9d) with the target terminal while dynamically allocating it an inherent IP address.
Unfortunately, because such a technology has not been developed yet, to be provided with the IP fax and IT services, etc., it is necessary for both terminals in order to be connected to the internet while each having to be allocated with an IP address.
For reference, the above-mentioned dial-up internet access terminal equipped with an ADSL modem is a terminal which complies with a protocol structure of an Internet Access Server (hereinbelow, referred to as xe2x80x9cIASxe2x80x9d) and a PPP/ATM.
Generally, the dial-up internet access terminal adapted for connection to the internet using the ADSL modem establishes the PPP session with the ISP while being dynamically allocated the IP address upon originating of a connection to the internet, and returns the allocated IP address to the ISP upon terminating of the connection from the internet.
Accordingly, in a state in which the dial-up terminal is connected to the internet, it possesses an inherent IP address, and a subscriber of the dial-up terminal can utilize a desired service or obtain necessary information through the internet.
In case of the connection of such a conventional dial-up internet access terminal to the internet, the subscriber of the dial-up terminal establishes a PPP session with the ISP while being dynamically allocated an IP address from the ISP, only if desired, for a connection to the internet.
Meanwhile, in case that a subscriber of a source terminal connected to the internet wants to utilize a service such as the IT together with a subscriber of a target terminal, if the target terminal is a dial-up terminal which has not been connected to the internet, the service between the source and target terminal cannot be executed.
There is therefore a need in the art for a technology that allows one internet terminal allocated with an IP address to call the other internet terminal allocated with no IP address, thereby providing both internet terminals with any internet service.
Therefore, the present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to provide an apparatus and method which enables a subscriber terminal connected to an internet while having an inherent IP address to communicate with a dial-up internet access terminal which has been allocated with no inherent IP address by establishing an IP level connectivity at any-time.
In an aspect of the present invention, there is provided an apparatus for providing an IP level connectivity between internet access terminals using a service gateway comprising: a first ISP network connected at one end thereof to a first terminal having an inherent IP address and at the other end thereof to an internet network, the first ISP network including a service gateway for executing authentication of a subscriber of the first terminal in accordance with a service request of the first terminal and communication with other service gateway; and a second ISP network connected at one end thereof to the internet network and at the other end thereof to an ATM network to which a second terminal having no inherent IP address is connected, the second ISP network serving to establish an IP level connectivity between the first and second terminals if the first terminal requests a connection to the internet network for service use along with the second terminal.
In another aspect of the present invention, there is also provided a method for providing an IP level connectivity between internet access terminals using a service gateway, comprising the steps of: establishing a first service gateway for executing authentication of a subscriber of a first terminal allocated with an inherent IP address and for allowing the first terminal to communicate with a second terminal by a request of the first terminal; establishing a second service gateway for executing authentication of a subscriber of the second terminal allocated with no inherent IP address and for allowing the first terminal to communicate with the second terminal by a request of the first terminal; requesting an assignment of the inherent IP address to be allocated to the second terminal if the second service gateway receives a request message for a connection between the first and second terminals from the first service gateway; and allocating the IP address requested in the requesting step to the second terminal, and transmitting the result of a connection of the second terminal to the internet network to the first terminal if the second terminal is connected to the internet network.